A senior White House official said Donald Trump wants Washington's European allies to use the 120-day period before some sanctions relief again comes up for renewal to agree on tougher measures.

A White House official said Donald Trump now wants to work with America's European allies. (File)

Washington:

US President Donald Trump grudgingly agreed not to reimpose nuclear sanctions on Iran on Friday, but officials warned that it would be the last time he issues such a waiver.

Instead, a senior White House official said, Mr Trump wants Washington's European allies to use the 120-day period before some sanctions relief again comes up for renewal to agree on tougher measures.

At the same time as the renewed waiver was announced, the US Treasury imposed sanctions on 14 Iranian figures and companies, including the head of the country's judiciary, Sadegh Amoli Larijani.

"The president's decision is to waive once more the nuclear sanctions that the terms of the JCPOA require the United States to waive in order to remain in the deal," the White House official said.

"But in his statement, the president will also make clear that this is the last such waiver that he will issue."

The official said that Mr Trump now wants to work with America's European allies - who all urged him to remain within the accord - to develop a new agreement to replace the Iran deal.

Tehran would not be involved in these discussions, as it was prior to the signing of the 2015 accord, but would be subject to US and European sanctions if it breaks the terms of the new arrangement.

The new deal, the official said, would be permanent and would not begin to expire after a decade as was the case in the 2015 accord.

It would target Iran's missile program and not simply its nuclear industry, and it would mandate UN inspections of Iranian sites.

"If the president can get that agreement that meets his objective and it never expires, it denies Iran all paths to nuclear weapons forever, not for ten years, he would be open to remaining in such a modified deal," the official said.

It would target Iran's missile program and not simply its nuclear industry, and it would mandate UN inspections of Iranian sites.

"If the president can get that agreement that meets his objective and it never expires, it denies Iran all paths to nuclear weapons forever, not for ten years, he would be open to remaining in such a modified deal," the official said.